Method oe producing metal tubes



THOMAS E. MURRAY, JR, 015 BROOKLYN, NEW YORK.

METHOD OF PRODUCING METAL TUBES.

Specification of Letters Patent.

Patented July 15, 1919.

Application filed February 6, 1819. Serial No. 275,288.

'1 '0 all whom it may concern:

Be it known that I, THOMAS E. MURRAY, J r., a citizen of the UnitedStates, residing at Brooklyn, in the county of Kings and State of NewYork, have invented a certain new and useful Improvement in Methods ofProducing Metal Tubes, of which the following is a specification.

The invention is a method of roducing metal tubes having walls ofvarying thickness, and consists in the steps hereinafter set forth.

In the accompanying drawings Figure 1 is a perspective view of one ofthe stepped blanks from which are made the two longitudinal halfsections of the desired tube. Fig. 2 is a perspective view of said tubewith the half sections separated. Fig. 3 is a perspective view of saidtube with the half sections welded and a thread cut on the thickerportion of the tube. Fig. 4 is a perspective view of one of the taperedblanks from which are made the two longitudinal half sections of thetube shown in Fig. 5, said last-named figure showing said sectionsseparated. Fi 6 is a erspective view of a grooved or c anneled lank, andFig. 7 is a perspective view of a half tube section formed from saidblank.

Similar letters of reference indicate like parts.

There are many uses for a metal tube, of which the wall is of varyingthickness or of difierent thicknesses. A simple example is found when itis desired to form a screw thread on a tube having a comparatively thinwall, which wall will not permit of the threading without an undesirableweakening of the wall. In such case I form a flat rectangular blank ofmetal, as shown in Fig. 1, havln a portion of its length A thicker thant e remaining portion Bor, in other words, step ed.

This blan k is to be of suflicient length and width so that when pressedor bent into semi-cylindrical form, as shown at C, Fig. 2, it willconstitute a lon itudinal half section of the desired tube. nother blankprecisely similar to that shown in Fig. 1 is pressed into semi-clindrical form, as shown at D, Fig. 2. T e two semi-cylindrical blanksare then placed with their edges in registering contact and areelectrically welded at said edges, as shown in Fi 3, to produce thecomplete tube. The thic er prtion A may then be threaded, as shown atWhere it is desired to produce a tube of tapered thickness, I prepare alongitudinally tapered plate, as shown at F in Fig. 4, and from two ofsuch plates form, by pressing, two precisel similar longitudinal halfsections G, H, Fig. 5, which being placed with their edges in contactregistry are electrically welded, as before.

If it be desired that the whole tube be taperedthat is, of less diameterat one end than at the other,I make the edge I of the blank shorter thanthe edge J so that the longitudinal edges converge, and weld thelongitudinal edges of the half sections, as before. The semi-circularedges I then form the smaller end and the semi-circular edges J thelarger end of the tube.

If it be desired to make a tube with a plurality of thicker portions-toform collars, for example,I prepare a blank plate, as shown in Fig. 6,with as many portions of increased thickness as may be required. In Fig.6 two such portions K, L are shown. The semi-cylindrical half section,Fig. 7, formed from such a plate is united by electrical welding to asimilar half section, as already descnbed.

I claim:

1. The method of makin a tube having its circumferential wall 0 varyingthickness, which consists in first forming two similar elongated platesof varying thickness, second, bending said plates transversely intosemi-cylindrical sha e, third, placin said bent plates with t eirlongitudin edges in registering contact, and, fourth, electricallywelding said registering edges together.

2. The method of making a tube having a portion of its circumferentialwall of greater thickness than elsewhere, which consists in first formintwo similar plates, each transversel divided into two sections ofdifierent thic ess, second, bending said plates transversely into semi-cylindrical shape, third, lacin said bent plates wit-h theirlongitudinal ges in registering contact, and, fourth, electricallywelding said registering edges to ether.

' The method 0 making a tube having portions of its circumferential wallof greater thickness than elsewhere, which consists in first formin twosimilar lates, each transversely divide into a plurality of sectionsalternately of greater and less thickness, second, bending said platestransversely into semi-cylindrical shape, third, placing said bentplates with their lon itudinal edges in re 'stering contact, and, ourth,electrically we ding said registering edges together.

4. The method of making a tube having its circumferential wall oftaperin thickness from end to end of said tube, which consists in firstforming two similar plates of gradually diminishing thicknesslongitudi-.

nally, second, bending said plates transversely into semi-cylindricalshape, third,

electrically We ding said registering edges is to ether.

n testimony whereof I have affixed my signature in presence of tWOWitnesses.

THOMAS E. MURRAY, J 1:.

Witnesses:

GERTRUDE T. PORTER, MAY T. MOLABRY.

Copies of this patent may'be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. G. t

